Effects of patient-level noise abatement orders on sound levels experienced by critically ill subarachnoid hemorrhage patients: an observational study

Background/Objective: Patients with aneurysmal subarachnoid hemorrhage (aSAH) may be at risk for complications related to excessive environmental noise. Our ICU utilizes a variety of universal interventions to minimize ambient noise levels, but patients with aSAH additionally have specific orders intended to further minimize physiologic stress and noise exposure. It is unknown whether such orders can have a supplementary reductive effect on noise exposure. Methods: Sound levels were measured for at least three consecutive days in the rooms of 17 patients with aSAH and implemented ‘subarachnoid precautions’ orders. Sound levels were similarly recorded in the rooms of 11 geographically-proximate, critically-ill control patients without aSAH. Results: Linear mixed models were used to assess the difference in measurements between groups. Observations were combined into fifteen-minute windows, then group means and their differences were calculated and plotted to help identify what times of the day had significant differences. aSAH patients consistently experienced lower sound levels than control patients, with a statistically significant difference (p < 0.05) in mean sound levels at 62 of 96 intervals throughout the day. Overall, the mean sound level for aSAH patients was always between 62–63dBA, while the mean sound level experienced by control patients ranged between 64–66dBA. Conclusions: Implementation of patient-specific orders can have a supplementary reductive effect on noise exposure for aSAH patients in an intensive care unit that already utilizes universal noise abatement interventions.